[PATCH net-next 11/12] net: hns3: prevent double free in hns3_put_ring_config()

From: Huazhong Tan
Date: Tue Apr 23 2019 - 23:23:48 EST


This patch adds a check for the hns3_put_ring_config() to prevent
double free, and for more readable, move the NULL assignment of
priv->ring_data into the hns3_put_ring_config().

Signed-off-by: Huazhong Tan <tanhuazhong@xxxxxxxxxx>
Signed-off-by: Peng Li <lipeng321@xxxxxxxxxx>
---
drivers/net/ethernet/hisilicon/hns3/hns3_enet.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
index 7dc281c..b0f31eb 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
@@ -3487,6 +3487,7 @@ static int hns3_get_ring_config(struct hns3_nic_priv *priv)
}

devm_kfree(&pdev->dev, priv->ring_data);
+ priv->ring_data = NULL;
return ret;
}

@@ -3495,12 +3496,16 @@ static void hns3_put_ring_config(struct hns3_nic_priv *priv)
struct hnae3_handle *h = priv->ae_handle;
int i;

+ if (!priv->ring_data)
+ return;
+
for (i = 0; i < h->kinfo.num_tqps; i++) {
devm_kfree(priv->dev, priv->ring_data[i].ring);
devm_kfree(priv->dev,
priv->ring_data[i + h->kinfo.num_tqps].ring);
}
devm_kfree(priv->dev, priv->ring_data);
+ priv->ring_data = NULL;
}

static int hns3_alloc_ring_memory(struct hns3_enet_ring *ring)
@@ -3920,8 +3925,6 @@ static void hns3_client_uninit(struct hnae3_handle *handle, bool reset)

hns3_dbg_uninit(handle);

- priv->ring_data = NULL;
-
out_netdev_free:
free_netdev(netdev);
}
@@ -4268,12 +4271,10 @@ static int hns3_reset_notify_init_enet(struct hnae3_handle *handle)
hns3_uninit_all_ring(priv);
err_uninit_vector:
hns3_nic_uninit_vector_data(priv);
- priv->ring_data = NULL;
err_dealloc_vector:
hns3_nic_dealloc_vector_data(priv);
err_put_ring:
hns3_put_ring_config(priv);
- priv->ring_data = NULL;

return ret;
}
@@ -4335,7 +4336,6 @@ static int hns3_reset_notify_uninit_enet(struct hnae3_handle *handle)
netdev_err(netdev, "uninit ring error\n");

hns3_put_ring_config(priv);
- priv->ring_data = NULL;

return ret;
}
--
2.7.4